Cass Mann is one of the world's longest-term HIV-positive diagnosed gay men, now in his third decade of living with HIV, and the founder of UK's only gay men's HIV/AIDS charity Positively Healthy, which provides HIV services including education, support, and peer counselling. Here he talks about how circuit parties revolve around a lot of drug use and unsafe sex. He recommends reading "Life Outside" by Michelangelo Signorile and "Sexual Ecology" by Gabriel Rotello to understand the issues. A person may come to a circuit party and leave with one or more sexually transmitted infections (STIs) including HIV. For more information, visit http://www.posh-uk.org.uk/ and http://www.AIDSvideos.org/.